Augustus sequeiea



(No Model.)

A. SEQUEIRA.

GENTERING GAGE.

@MQXLWE y M 444 m g 4m UNITED STATES PATEN OFFICE.

AUGUSTUS SEQUEIRA,OF HARTFORD, CONNECTICUT.

CENTERlNG -GAG E.

SPECIFICATION forming part of Letters Patent No. 271,746, dated February 6, 1883.

' Application filed October 16,1882. (No model.)

To all whom it may concern:

Be it known that I, AUGUSTUS SEQUEIRA, of Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Centering- Gagcs; and I do hereby declare that the following is a full, clear, and exact description thereof, whereby a person skilled in the art can, make and use the same, reference being rear view of thesame.

had to the accompanyingdrawings, and to the letters of reference marked thereon.

Like lettersin the figures indicate the same parts. l a

My improvement relates to gages for markin g a center-poin-t in the end of bars of metal or other objects for drilling the center-holes upon which such articles are turned in a lathe or supported in any other machine.

The object.- of my invention is to provide a simple and inexpensive tool which shall be adapted to fixing the centers upon bars of different forms and sizes. a

In the accompanyingdrawings, illustrating my invention, Figure 1 shows a front view of my improved centering-gage. Fig. 2 shows a Fig. 5 is a longitudinal section throughthe middle of the gage, showing more particularly its internal construction.

A is the fixed body of the gage. It is provided with the bow Aon the rear side, through whichis boredja cylindrical slot in which the center-punch slides back and forth at right angles to the face of the gage B is the center-punch, which has a shank fitting exactly in the socket in A, and which is provided with a conical point in the cus-' tolnary manner. The outer end of the punch is made a little larger than the shank. so that it will. not pass through the socket. Thispart is generally milled or roughened for convenience in handling.

O C are jaws for grasping and fixing the position of the object to be centered. They slide out and in radially through sockets in the frame or body A." They areintended to be of a cylindrical form, as shown in the drawings, and are provided at their inner ends with angular openings U, for embracing the object to be centered. The rear sides of these jaws are cut into racks D D, by means of which the jaws are moved and held firmly in position.

E is the ring, which fits upon a circular bear- J ing on the frame A,just back of the jaws G.

This ring is furnished on its face with a scroll or spiral, which fits into the teeth of the racks upon thejaws in such a manner that when the to enable it to beturned readily by hand.

The operation of my invention is as follows:

When the ring E is turned the scroll on its face acts upon the racks on the jaws O and moves them simultaneously out or in a radial direction, so that the hearings on the inner ends are always exactly the same distance from the center. When it is desired to center any object it is placed between the jaws and the ring E turned to bring the jaws together, so as to touch at opposite points. The center-punch is then struck by a mallet or hammer to make a mark upon the end of the bar or other object held. This gives the point for the holeto be drilled in the customary manner. My improved gage is adapted to mark the center-point upon bars of various shapes as well as sizes. A round bar is embraced by the wyes on the inner ends of the jaws. A square or rectangular bar is embraced by two corners at opposite ends of a diagonal. A polygonal bar lS ClllbIflCGd by two oppositeangles. This result is obtained by having only two jaws, and causing them to I 

